Manteca leaders: Twin tunnels put water in jeopardy

The Delta Twin Tunnel plan could rob Manteca of water it has contractually tied up from the Stanislaus River basin.

That’s the fear that the Manteca City Council has of the Delta water solution being pursued by Southern California and Bay Area urban water interests as well as large southern San Joaquin Valley farming concerns.

Mayor Willie Weatherford noted construction of the $24.54 billion update of the 1980 Peripheral Canal proposal is being justified by three goals: Saving the Delta, preserving wildlife, and sending more water south.

Weatherford pointed out that it is impossible to obtain all three goals without an increase in available water.

The City Council touched on the proposed 35-mile tunnel that would stretch from a point on the Sacramento River near Hood to the Tracy pumps during a discussion last week on Manteca’s future water supplies.

Manteca is contracted with the South San Joaquin Irrigation District for up to 18,500 acre feet of water per year that would accommodate the equivalent of 25,000 more homes. Even though the SSJID has historical — and superior — water rights, the council fears the courts could overturn existing rights if water bound for Los Angeles bypasses the Delta and replacement water is needed to prevent an ecological disaster.

Among the council’s concerns are that the Twin Tunnel plan will:

• increase salt water in the Delta to the detriment of the environment.

• increase sale water intrusion in underground aquifers. During the drought in the 1990s increased salinity was found as far away from the Delta as wells near Jack Tone Road.